已知等差数列{an},{bn}满足an/bn=2n/(3n+5),它们的前几项之和分别记为Sn和Tn,求S11/T11的值(要过程)
人气:231 ℃ 时间:2020-05-11 13:39:11
解答
S11/T11=(a1+a11)/(b1+b11)=a6/b6=12/23
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